4.3 USPTO Guidelines and Training Materials on Written Description Requirements

1. For each claim determine what the whole claim covers; [40]
2. Review the entire application to understand how the applicant provides support for the claimed invention including each element and/or step; and
3. Determine whether there is sufficient written description to inform a skilled artisan that the applicant was in possession of the claimed invention as a whole at the time the application was filed.

The claimed invention as a whole may not be adequately described if the claims require an essential or critical feature which is not adequately described in the specification and which is not conventional in the art or known to one of ordinary skill in the art. This problem may arise where an invention is described solely in terms of a method of its making coupled with its function and there is no described or art-recognized correlation or relationship between the structure of the invention and its function. A lack of adequate written description also arises if the knowledge and level of skill in the art would not permit one skilled in the art to immediately envisage the product claimed from the disclosed process. [41]

1. Claims to “an isolated gene comprising sequence SEQ ID NO: 1” will not be regarded as having an adequate written description unless one skilled in the art knows or the specification contains information about the nature of all parts of the “gene” as defined by the applicant, including where appropriate regulatory elements and untranslated regions if these are necessary for the DNA in question to function as a “gene”. [42]

2. Similar conclusions are reached where the claim is to “An isolated DNA comprising SEQ ID NO: 1", (for example an expressed sequence tag or EST) where the “comprising” language means that the claim could, for example include an entire gene containing the stated sequence event though this represents only a small part of the gene as a whole.

3. Claims to “isolated nucleic acid that specifically hybridizes under highly stringent conditions to the complement of the sequence set forth in SEQ ID NO:1" will be regarded as having a sufficient support in the written description if a specific utility is described for the DNA (for example that it codes for a protein having a described credible substantial and specific utility) and proteins expressed from the isolated nucleic acids hybridizing with the defined sequence under such stringent conditions are reported to have the same properties.

4. On the other hand, problems can arise with even this type of claim if the function is defined too broadly or to something specific which is not adequately described. Thus the Training Materials indicate that claims directed to Isolated mammalian cDNA encoding insulin and to a sub claim defining the mammalian cDNA as being human should both be rejected as lacking a written description if the only cDNA’s actually described are rat DNAs. The commentary indicates that the reason for this was a lack of knowledge as to the relationship of rat DNA to those of other mammals.

5. Claims to allelic variants without specifying the nature of the variation (e.g. single nucleotide polymorphisms or SNPS - such as “An isolated allele of some defined piece of DNA” ) are likely to be rejected on the basis that the art is at present sufficiently unpredictable that one would not know the functional properties of any protein produced nor how the structure of one allele might be representative of another. The situation might be slightly better if the claim were to specify the protein for which the allele must code. Even here, however the training materials indicate that since in the present state of the art the structure of one allele does not provide guidance to the structure of others, one cannot conclude that the inventor was in possession of the claimed genus of all alleles of the defined DNA having the stated property.